/
ɪˈkweɪtə/
n.
a line notionally drawn on the earth equidistant from the poles, dividing the earth into northern and southern hemispheres and constituting the parallel of latitude 0°.
▸short for celestial equator.
Etymology
ME: from med. L. aequator, in the phr. circulus aequator diei et noctis ‘circle equalizing day and night’, from L. aequare (see equate).